There should be more viable option to getting lobi crystals like mission rewards and drops. Limiting to lock boxes will require players to buy zens to open these lock boxes the keys are $5.99. Real money should never be spent for ingame items. just consider my suggestion for the game.

Limiting to lock boxes will require players to buy zens to open these lock boxes the keys are $5.99. Real money should never be spent for ingame items.

This is pretty much the basis of the F2P model. Play the game for free, pay money for lifestyle improvements. You don't HAVE to get the Rule 62 console or a Recluse , they're just nice to have. Endgame is perfectly capable of being played using any existing items that can be purchased from the Shipyard using dilthium and/or from the Exchange.